This application contains a five-year research training program for the development of an academic career in neurophysiology and medicine. The candidate completed a Master's in Biology in 1993 at the George Washington University and an emergency medicine residency at the University of New York, Stony Brook Campus in 2000. Throughout his tenure as a graduate student, medical student, resident and attending, the applicant has continued to be involved in research. The described training program is designed to provide the candidate with the didactic and practical experience necessary for him to become an independent investigator in the fields of toxicology and neurophysiology. The scientific aims of this investigation focus on characterizing the central nervous system physiologic effects of organophosphate (OP) and nerve agents. Prior research has shown that patients poisoned with organophosphate poisons simply stop breathing. The PI has chosen Dr. David Paydarfar as a mentor for this project. As a practicing research physician at the University of Massachusetts, Dr. Paydarfar has extensive experience in respiration-related neurophysiology. The candidate's research efforts will focus on determining the mechanism by which organophosphates and nerve agents exert their effects on respiration. First, the candidate plans to test the hypothesis that death from acute organophosphate poisoning is caused by apnea due to acute loss of rhythmic output of the central respiratory oscillator in the brainstem. Phrenic nerve output will be determined in rats pretreated with glycopyrrolate undergoing either, sham surgery (controls), bilateral vagotomy, bilateral decerebration or both prior to OP with dichlorvos poisoning. A second set of hypotheses examine this same research question using an OP chemical warfare agent. A third hypothesis examines practical treatments for OP poisoning. Compounds suggested by preliminary research or prior publications will be systematically explored in the animal models described in Specific Aims 1 and 2. Gross mortality rates, phrenic nerve output and physiologic parameters will be measured in rats treated with compounds identified to be effective in OP poisoning. It is our expectation that by better understanding the mechanism of OP induced respiratory depression, prophylactic strategies to prevent mortality from OP in exposed individuals or those at high risk for exposure can be developed. The combination of training in the Departments of Neurology and Emergency Medicine at the University of Massachusetts Medical School provide an ideal setting and furthermore allow access to the facilities, equipment and expertise necessary to achieve the goals set forth in this proposal. The goal of the applicant is to become an independent researcher in the area of neurophysiology and neurotoxicology with the ability to run his own laboratory and write successful grant applications.